Police arrested 109 people during opposition protests on the sidelines of an official demonstration marking three decades since the seizure of the US embassy, Tehran's police chief said on Saturday.

Police arrested 109 people during opposition protests on the sidelines of an official demonstration marking three decades since the seizure of the US embassy, Tehran's police chief said on Saturday.

"A hundred and nine people were arrested. Forty-seven were released on bail and 62 are in prison and their files are with the judicial authorities," General Azizollah Rajabzadeh was quoted as saying by the Mehr news agency.

Among those jailed are "43 men and 19 women," he said.

Police on Wednesday fired tear gas in central Tehran to disperse groups of protesting opposition supporters as thousands of Iranians staged the annual anti-US rally outside the former US embassy building to mark the 30th anniversary of its storming by Islamist students.

The opposition has since June been staging protests in the capital against the re-election of President Mahmoud Ahmadinejad in a presidential poll they claim was massively rigged.